1. Field of Invention
This invention relates to plant receptacles, specifically to an improved construction using wood for planter boxes which employs a knockdown frame to hold panels of materials other than wood.
2. Description of Prior Art
Wooden Planter boxes in the past have been entirely constructed out of wood, and in particular, redwood. Redwood enjoys a false reputation for being impervious to decay in contact with soil and moisture. In reality, all indigenous species of wood rot relatively quickly under these conditions. Consequently, any conventional wooden planter box needs periodic replacement.
Because they inevitably rot, wooden boxes have sometimes been lined with thin metal sheets. These are metals, such as copper or galvanized steel. Metal protects the wood from decay, but such linings are expensive to fabricate.
Wooden planter boxes have shipped in fully assembled form. One assembly method utilizes wooden sides which are held in restrained in position by a tensioned metal strap. Another method utilizes tongue and groove construction to hold wooden planks together. One example of prior art, U.S. Pat. No. 4,9001,473, may be disassembled and assembled in knockdown form and utilizes a frame, post and panel construction. It is constructed preferably of metal and it utilizes an interlocking construction of tongues and hooks. Another, U.S. Pat. No. 1,407,664, discloses an enclosure in which rest either sides comprising either discrete vertical slats or a one-piece earthenware container, both of which allow water to drain through a perforated bottom into a drip pan.
Shipping costs add much to the expense of marketing planter boxes because of the volume they occupy. Most of the volume of an assembled planter box is empty space. It would be a decided advantage to be able to ship knockdown parts as an alternative. U.S. Pat. No. 3,955,320 discloses a wooden planter box which may be shipped in knockdown form.
One way to prevent planter box rot is to construct the boxes of plastic. As an additional advantage, plastic planters may be nested for shipping purposes. However, plastic does not have the aesthetic appeal of wood and plastic production depletes non-renewable oil resources.
Recently, the increased cost of wood in general, and of redwood in particular, makes manufacturing planter boxes very expensive. This, plus its vulnerability to rot and decay and the resultant waste of material raises questions about the continued suitability of redwood for this application. Environmental issues have also been raised surrounding dwindling redwood resources. A major advantage for a planter box would be to enable side panels to be easily removed to enable root pruning entirely without removing the soil. Only one design, which is embodied in planter boxes found in the Orangerie in Versailles, France, permits this. This cumbersome and expensive planter box is referred to as the Caisse de Versailles, and utilizes iron straps and iron fasteners on removable oak side panels.